Such methods are employed in the processing of digital microscope images that are obtained using a digital camera of a microscope. One example is a microscope image of a tissue specimen that was recorded in an enlargement with a microscope and that is selected in a size such that a plurality of partial images is necessary to obtain a microscope image of the entire tissue specimen in the desired enlargement. A computing operation, such as, for instance, finding the mean brightness, in particular in a plurality of partial areas, is to be applied to this digital microscope image that is present in partial images.
U.S. Pat. No. 4,673,988 A1 describes a method for producing such an electronic mosaic image using a microscope. The mosaic image has a high resolution in a wide image field. For recording the mosaic image, in addition to a first camera the microscope includes an image recording means. The specimen for which a mosaic image is to be recorded is moved in a controlled manner in a grid using the image recording means and at previously calculated positions individual partial images are recorded that are then combined to create a microscope image. What this achieves is that the individual partial images do not overlap.
In known methods for processing a digital microscope image, the entire microscope image is loaded into the working memory of the computer and is then processed by a processor of the computer. However, since the entire microscope image is too large to be loaded in its entirety into the, where necessary virtual, working memory of the computer, the microscope image is stored in part on the mass storage device. Such a method is called swapping or paging in English. For it to be possible to execute the computing operation, the image parts must first be re-loaded into the working memory.
It is disadvantageous in such methods that paging is controlled solely by the operating system of the computer, which can lead to image data that could be paged being held in the working memory. Since the mass storage device has a longer access time than the working memory and swapping or paging is time-intensive, this slows processing of the microscope image, which is disadvantageous.
Moreover, a microscope image can be so large that the address space of the processor is not sufficient for loading the microscope image into the working memory so that the microscope image itself cannot be held in the working memory by swapping or paging using the operating system.
In known methods, if the microscope image is so large that it cannot be held in its entirety in the working memory, the partial images are processed individually. The result of this is that either the information about the adjacent partial images is not taken into account, so that inaccuracies occur on the edge, or special algorithms must be worked up to solve this problem of inaccuracies. Frequently these inaccuracies are simply accepted. Then separate algorithms must be found for solving the accuracy problems on the edge.